The invention relates to a domestic electrical vacuum cleaner consisting of an appliance housing, a suction hose releasably secured thereto with a suction tube fitted thereon and a suction nozzle, the suction tube and/or suction nozzle being connectable to the appliance housing by means of a coupling device.
Vacuum cleaners of the type described above are known. By means of a retaining device, e.g. a pouch formed on the appliance housing into which a hook secured to the suction tube or suction nozzle can engage, these tools, which are absolutely essential for a domestic vacuum cleaner, can be attached to the appliance housing during periods of non-use. As a result of the tidy condition of the entire vacuum cleaner unit which can be achieved in this way at times of idleness of the appliance and the possibility of transportation from one room to another or from one floor to another, the risk of an accident caused by the vacuum cleaner is substantially reduced and the storage space at times of non-use of the domestic electrical appliance is reduced to a minimum without the need to take the vacuum cleaner apart. A vacuum cleaner equipped with a retaining device of this kind remains fully operational at all times.
The vacuum cleaner which comes closest to that of the invention is one which has a releasably attached accessory part. In this known vacuum cleaner, a suction nozzle and an extension tube are fixed to one wall of the vacuum cleaner housing. In order to enable the above-mentioned accessory parts to be fixed using means which are easy to produce and handle, an elongate guide rail which is at least substantially T-shaped in cross section is secured by its central web to the accessory part. In the appliance housing is a mating guide groove having a suitably mating profile and open on its front side at one end. The guide rail can be inserted in the mating guide groove and operatively attached in this way (DE-OS 35 29 133).
A particular disadvantage which has been found with this known vacuum cleaner with its attached accessory part is the fact that the accessory part can only be uncoupled in one direction. Any deviation from the direction of uncoupling is ruled out. If the proper direction of coupling is not observed, the T-shaped central bar tilts out of position in its mating guide groove. As a result, either the accessory part cannot be uncoupled and the entire vacuum cleaner housing together with the accessory part attached thereto will be lifted. However, there is also the possibility that if force is applied in a direction other than the direction of uncoupling, particularly as a result of the intensification of force through the lever arm of the suction tube, the forces acting on the coupling region will exceed the breaking strain of the T-shaped guide rail or the housing in the region of the mating guide groove. In this event, material fractures will occur either in the T-shaped guide rail or in the guide groove located in the housing of the appliance.